A sanitary washing toilet seat device retractably houses therein a washing nozzle for squirting wash water, and hence, in the mainstream configuration, it is installed for use on the rear upper surface of a sit-down toilet bowl. For the purpose of improving the cleanability of such a sanitary washing toilet seat device, its downsizing is under study. More specifically, a smaller depth dimension of the sanitary washing toilet seat device allows the portion overlying the bowl of the sit-down toilet bowl to be reduced, saving trouble to clean the backside of the sanitary washing toilet seat device overlying the bowl. Furthermore, a smaller height of the sanitary washing toilet seat device allows the soiled area to be reduced, also facilitating cleaning.
To downsize the sanitary washing toilet seat device, the dimension of the washing nozzle in the housed state needs to be decreased. As a structure for decreasing the dimension of the washing nozzle in the housed state, the multistage structure is desirable. As an extension/retraction mechanism of the multistage washing nozzle, use of water pressure and a wire is disclosed, for example (Patent Document 1).
On the other hand, as an extension/retraction mechanism of the washing nozzle, also disclosed is a structure in which a leaf spring is wound around a drum rotated by a motor and is advanced/retracted by the rotation of the motor to extend/retract the nozzle (Patent Document 2).    Patent Document 1: Japanese Unexamined Utility Model Application Publication No. 61-32267    Patent Document 2: Japanese Unexamined Patent Application Publication No. 59-102031